From 0161108e8733ed5735548ec55c9b021147c62e52 Mon Sep 17 00:00:00 2001
From: sairajzero <sairaj0630@gmail.com>
Date: Mon, 30 Aug 2021 22:02:11 +0530
Subject: [PATCH] Create database.js

---
 src/database.js | 86 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 86 insertions(+)
 create mode 100644 src/database.js

diff --git a/src/database.js b/src/database.js
new file mode 100644
index 0000000..b237267
--- /dev/null
+++ b/src/database.js
@@ -0,0 +1,86 @@
+'use strict';
+var mysql = require('mysql');
+
+function Database(user, password, dbname, host = 'localhost') {
+    const db = {};
+
+    Object.defineProperty(db, "connect", {
+        get: () => new Promise((resolve, reject) => {
+            db.pool.getConnection((error, conn) => {
+                if (error)
+                    reject(error);
+                else
+                    resolve(conn);
+            });
+        })
+    });
+
+    Object.defineProperty(db, "query", {
+        value: (sql, values) => new Promise((resolve, reject) => {
+            db.connect.then(conn => {
+                const fn = (err, res) => {
+                    conn.release();
+                    (err ? reject(err) : resolve(res));
+                };
+                if (values)
+                    conn.query(sql, values, fn);
+                else
+                    conn.query(sql, fn);
+            }).catch(error => reject(error));
+        })
+    });
+
+    Object.defineProperty(db, "TxQuery", {
+        value: (queries) => new Promise((resolve, reject) => {
+            db.connect.then(conn => {
+                conn.beginTransaction((err) => {
+                    if (err)
+                        conn.rollback(() => {
+                            conn.release();
+                            reject(err);
+                        });
+                    else {
+                        (function queryFn(result) {
+                            if (!queries.length) {
+                                conn.release();
+                                resolve(result);
+                            } else {
+                                let q_i = queries.shift();
+                                const callback = function(err, res) {
+                                    if (err)
+                                        conn.rollback(() => {
+                                            conn.release();
+                                            reject(err);
+                                        });
+                                    else {
+                                        result.push(res);
+                                        queryFn(result);
+                                    }
+                                };
+                                if (q_i[1])
+                                    conn.query(q_i[0], q_i[1], callback);
+                                else
+                                    conn.query(q_i[0], callback);
+                            }
+                        })([]);
+                    }
+                });
+            }).catch(error => reject(error));
+        })
+    });
+
+    return new Promise((resolve, reject) => {
+        db.pool = mysql.createPool({
+            host: host,
+            user: user,
+            password: password,
+            database: dbname
+        });
+        db.connect.then(conn => {
+            conn.release();
+            resolve(db);
+        }).catch(error => reject(error));
+    });
+}
+
+module.exports = Database;
\ No newline at end of file